Mr Markle upset Meghan by staging paparazzi photos in the run up to the big day, although a heart operation was the reason given for his non-attendance.

Last month, Samantha Markle said she feared her father would "die of sadness" if he didn't see Meghan again.

Ms Markle said: "I'm desperate for Meghan to meet up with Dad when she's back. If she doesn't it would be really cruel and hurtful and would break his heart.

"I speak to him every day. He's very sensitive and I see his health suffering as a result of this. I hope they can meet in a quiet place, spend some quality time together and gain closure on what's been an incredibly sad time for him.

"If they don't I'm worried he'll die of sadness. I just want her to get in touch before it's too late. Life's short - neither of them deserves to be left with the consequences."

In an interview with The Sun, Mr Markle compared the royal family to Scientologists because of their "cult-like" secrecy.

Samantha Markletweeted these photos of her and estranged half-sister, Meghan. Picture: Twitter

Meghan and Harry are reportedly refusing to be drawn into a war of words with her father after his public criticism of the couple in recent weeks, reports The Sun.

However, sources have now told The Sunday Times that the frustrated couple will not try and set the record straight with him.

One told the paper: "Meghan doesn't think it's a fair game between her father and the media so she's not going to engage in it or instruct anyone on her behalf to set the record straight.

"There have always been fears over his vulnerability.

"Now he's got himself into a cycle of talking publicly. It's very sad."

Another source close to Prince Charles added: "The prince will be very sympathetic towards Meghan and the difficult situation she is in.

"But I suspect the Queen will be rolling her eyes and thinking: crikey, what is going to become of all this?"

Meghan is not believed to have spoken with her dad, 74, since shortly after the wedding when she and Prince Harry scolded him for secretly staging photoshoots.

Meanwhile, Mr Markle has hit out at a number of "outright lies" against him, such as that he is a prescription pill addict.

Speaking from his home in Mexico, he told The Mail on Sunday: "I've given just three interviews but there are thousands of stories circulating out there and it's not right that people should be allowed to make up lies and get away with it.

"I've read stories saying I'm a drug addict or alcoholic. I don't understand where these stories come from. I've taken pills when I've been in pain but I've never abused drugs.

"You couldn't move in Hollywood in the 1980s without seeing bowls of cocaine everywhere. But I don't do drugs and I barely drink."

And Meghan's uncle has revealed his distress at not being invited to the royal wedding.

Michael Markle, a former US diplomat, was "surprised" he didn't make the guest list and branded his exclusion a "snub" by the royal family.

Meghan and Harry reportedly aren’t going to engage in a public debate with the markles. Picture: WireImage

Despite his health problems, the he told the Sunday Mirror he would have flown to Windsor from his home in Florida for his niece's big day.